Liquid drain opening composition and method

ABSTRACT

AN AQUEOUS SOLUTION OF BETWEEN ABOUT 1% AND 9% BY WEIGHT SODIUM OR POTASSIUM HYPOCHLORITE AND BETWEEN ABOUT 2% AND 9% BY WEIGHT SODIUM OR POTASSIUM HYDROXIDE PROVIDES A VERY EFFECTIVE DRAIN OPENER WHICH IS NOT AS HAZARDOUS TO USE AS THE CONVENTIONAL HIGHLY CONCENTRATED CAUSTIC DRAIN OPENERS. BETWEEN ABOUT 1% AND 7% BY WEIGHT SODIUM OR POTASSIUM CHLORIDE IS PRESENT IN THE SOLUTION, AND THE POTASSIUM ION CONCENTRATION IN THE DRAIN OPENER SOLUTION IS IN EXCESS OF THE SODIUM ION CONCENTRATION. SODIUM OR POTASSIUM SILICATE MAY BE INCLUDED IN THE DRAIN OPENER SOLUTION TO INHIBIT THE CORROSIVE ACTION OF THE SOLUTION UPON METAL PLUMBING FIXTURES, AND A SMALL AMOUNT OF A WETTING AGENT, OR IN OTHER WORDS SURFACE ACTIVE AGENTS, INCREASES THE RATE AT WHICH THE DRAIN OPENER SOLUTION PENETRATES FATTY MATERIAL.

United States Patent 3,697,431 LIQUID DRAIN OPENING COMPOSITION ANDMETHOD Vernon E. Summerfelt, South San Francisco, Calif., as-

signor to The Clorox Company, Oakland, Calif. N0 Drawing. Filed Jan. 22,1971, Ser. No. 109,057

Int. Cl. C11d 7/54 U.S. Cl. 252-403 2 Claims ABSTRACT OF THE DISCLOSUREAn aqueous solution of between about 1% and 9% by weight sodium orpotassium hypochlorite and between about 2% and 9% by weight sodium orpotassium hydroxide provides a very effective drain opener which is notas hazardous to use as the conventional highly concentrated causticdrain openers. Between about 1% and 7% by weight sodium or potassiumchloride is present in the solution, and the potassium ion concentrationin the drain opener solution is in excess of the sodium ionconcentration. Sodium or potassium silicate may be included in the drainopener solution to inhibit the corrosive action of the solution uponmetal plumbing fixtures, and a small amount of a wetting agent, or inother words surface active agent, increases the rate at which the drainopener solution penetrates fatty material.

BACKGROUND OF THE INVENTION Drains for kitchen and bathroom sinks oftenbecome clogged by a combination of fatty substances and protein fiberswhich are usually present in the form of hair or food particles. Thecombination of fat and protein fiber provides a water insoluble masswhich is difficult to dislodge or dissolve. Most liquid drain openers incommon use are composed primarily of a concentrated solution of a strongbase or acid. In the case of a conventional strong base drain opener,generally a hydroxide concentration of between about 20% and 40% byweight is utilized in order to convert fats in the drain to soap andalso to attack the protein fibers. However, if such concentrated drainopeners accidentally come in contact with people or clothing, injury tothe person or damage to clothing may result unless prompt remedialaction is taken. Such concentrated hydroxide solutions are particularlydamaging to eyes. Furthermore, concentrated sodium hydroxide drainopeners react with fats in drains to form a hard, sodium soap which isalmost as difiicult to dislodge as the fatty material which originallyclogged the drain.

SUMMARY OF THE INVENTION It has now been found that a combination ofhypochlorite and hydroxide provides a drain opener which is moreeffective and less hazardous than the concentrated hydroxide drainopeners now in common use even though the combined amount ofhypochlorite and hydroxide is less than the amount of hydroxide requiredin an effective conventional hydroxide drain opener. In accordance withthis invention an excellent drain opener is provided by an aqueoussolution of between about 1% and 9% by weight of sodium or potassiumhypochlorite, and between about 2% and 9% by weight sodium or potassiumhydroxide, in which solution the potassium ion concentration is inexcess of the sodium ion concentration. As long as the potassium ionconcentration from all compounds in the drain opener solution is inexcess of the sodium ion concentration, the soap formed within the drainis soft and dissolves relatively quickly compared to the hard and lumpysoap formed if sodium is the sole or predominant cation.

The drain opener solution contains between about 1% and 7% by weightsodium or potassium chloride which 3,697,431 Patented Oct. 10, 1972reduces the corrosive effect of the drain opener on the metal plumbingfixtures. Also, up to about 10% of sodium or potassium silicate isadvantageously added to the drain opener solution as a corrosioninhibitor. If the silicate is added for this purpose, at least 3% byweight is an effective corrosion inhibitor and provides substantialprotection for fittings containing zinc and aluminum against the attackof the caustic.

A Wetting agent, or in other words a surface active agent, may beincorporated in the drain opener solution to increase the rate at whichthe drain opener penetrates the mass of fat and protein fibers whichclog drains. Any wetting agent which is compatible with the hypochloriteand hydroxide in the drain opener may be used. If a wetting agent isemployed in the drain opener solution, between 0.25% and 1% by weight iseffective.

In use the drain opener solution is generally diluted by water which ispresent in the drain or sink. However, the drain opener hereof iseffective even though it is diluted between one and three or four timesby the water which is retained in a stopped drain or sink.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In greater detail the drainopener solution contains between about 1% and 9% by weight of sodium orpotassium hypochlorite. If less than about 1% by weight of hypochloriteis utilized, the drain opener loses much of its effectiveness anddisintegrates protein fibers very slowly, particularly when the drainopener solution is diluted by water usually present in the drain orsink. If more than 9% by weight hypochlorite is used, the drain openerbecomes increasingly and unnecessarily corrosive and hazardous to peopleand materials. Furthermore, such concentrated hypochlorite solutions aremore unstable and tend to deteriorate faster.

Sodium or potassium chloride is a by-product in the manufacture ofhypochlorite. As a result the hypochlorite incorporated in the drainopener solution inherently contains between about 1% and 7% by weightsodium or potassium chloride. At low hypochlorite concentrations,additional chloride may be added to the solution because the chloridesalt reduces the corrosive effect of the drain opener on fittingscontaining zinc and aluminum.

The sodium or potassium hydroxide in the drain opener saponifies fatswhich clog drains and converts the fats to water soluble soap. Between2% and 9% by weight sodi um hydroxide is used. Lower concentrations arenot very effective in dissolving fats when diluted by the water usuallypresent in sinks and drains. If more than 9% by weight hydroxide is usedin the drain opener solution, the drain opener presents hazards to theeyes, and it causes excess corrosion of fittings containing aluminum andzinc which are present in plumbing fixtures, as well as in garbagedisposal units.

Although the drain opener hereof is not relatively corrosive orhazardous because of the low concentration of hypochlorite and hydroxideutilized, sodium or potassium silicate is advantageously added to evenfurther reduce the hazards and corrosiveness of the solution. Theconcentration of silicate may vary between zero and 10% by weight, butfrom between about 3% and 10% by weight of silicate is preferable. 3% ofsilicate in the drain opener solution is sufficient to provide asignificant reduction of the corrosive effect of the drain opener uponmetals. If more than 10% silicate is used, little further benefit isobtained.

A wetting agent, or in other words a surface active agent, ispreferably, but not necessarily, incorporated in the liquid drainopener. The wetting agent increases the rate at which the drain openerpenetrates the fatty substance which clogs drains. About 0.25% by weightwetting agent is effective to provide a significant increase in the rateof penetration of fatty material. Up to 1% by weight of wetting agentmay be utilized, but if a greater amount is employed deterioration ofthe hypochlorite is accelerated. A wetting agent that is compatible withthe hypochlorite and hydroxide in the drain opener solution is utilized.For example, the anionic mono phosphate ester of ethoxylated alcohol,sold under the name Gafac CD- 178 by GAF Corporation, may beincorporated in the drain opener. Another example of a suitable wettingagent is the salt of a perfluoro acid sold by Minnesota Mining andManufacturing Company under the name Fluorad 50-98.

The potassium ion concentration provided by all compounds present in thedrain opener solution should exceed the sodium ion concentration. If thepotassium ion concentration is in excess of the sodium ionconcentration, the soap which is formed by saponification of the fat issoft and porous, rather than hard and lumpy. The soft and porous soapdisperses in water much more rapidly than the hard and lumpy soap formedif sodium is the predominant cation.

The remainder of the drain opener solution is made up of water. In otherwords, water may make up as much as 96% by weight of the drain opener.However, other inert ingredients may also be present.

The drain opener solution is prepared simply by mixing the ingredients,namely the hypochlorite solution, hydroxide solution, and othercomponents until they are completely dissolved to form a drain openersolution having the desired composition. Generally the order of mixingis not critical. However, when an acidic wetting agent is used, itpreferably should be added to a neutral solution. In that case thehypochlorite and hydroxide are mixed first, followed by the wettingagent and then the silicate.

In the following examples of the drain opener, solutions were applied tosolid mixtures of four grams of vegetable fat and two grams of humanhair. One part of water for each one part of drain opener solution wasalso added so that the drain opener would be diluted and the testconditions would be similar to the conditions often present with stoppeddrains. The effect of the drain opener upon the solid clogging mixtureover a period of time was noted. All percents in the examples are givenin terms of percent by weight.

The hair was dissolved in 1 hour, and the fat within 3 hours, therebyindicating that the solution was an effective drain opener.

EXAMPLE 2 Percent Sodium hypochlorite 1.4 Potassium hydroxide 1.0 Sodiumchloride 0.9 Water 96.7

The hair was dissolved in 1 hour, but the fat was not dissolved in 8hours, because the amount of hydroxide was less than specified for thedrain opener hereof.

EXAMPLE 3 Percent Sodium hypochlorite 4.6 Potassium hydroxide 4.5Potassium silicate 6.0 Sodium chloride 3.6 Wetting agent 0.25 Water81.05

The hair was dissolved in 1 hour, and the fat within 5 hours, therebyindicating the solution was an effective drain opener.

The hair was dissolved in 1 hour, and the fat within 5 hours, therebyindicating the solution was an effective drain opener.

EXAMPLE 5 Percent Sodium hypochlorite 5.0 Sodium hydroxide 4.0 Sodiumsilicate 8.0 Sodium chloride 3.9 Wetting agent 0.25 Water 78.85

Both the hair and fat were only partially dissolved in 5 hours therebyillustrating the disadvantage of a sodium ion system as compared to thepotassium ion system in Example 4.

EXAMPLE 6 Percent Sodium hypochlorite 9.0 Potassium hydroxide 2.0Potassium silicate 10.0 Sodium chloride 7.05 Wetting agent 0.25 Water71.70

Hair rapidly dissolved in less than an hour, and the fat was partiallydissolved in 3 hours.

What is claimed is:

1. A liquid drain opener solution consisting essentially of an aqueoussolution of between about 1% and 9% by weight of an alkali metalhypochlorite selected from the group consisting of sodium hypochloriteand potassium hypochlorite, between about 2% and 9% by weight of analkali metal hydroxide selected from the group consisting of sodiumhydroxide and potassium hydroxide, between about 1% and 7% by weight ofan alkali metal chloride selected from the group consisting of sodiumchloride and potassium chloride, between about 3% and 10% by weight of awater soluble alkali metal silicate selected from the group consistingof water soluble sodium silicate and water soluble potassium silicate,and between about A% and 1% by weight of a wetting agent compatible withsaid hypochlorite and said hydroxide, the concentration of potassium ionbeing in excess of the concentration of sodium ion in said solution.

2. The method of openinga drain clogged by fats and protein fibers whichcomprises pouring into said drain the drain opener solution of claim 1.

References Cited UNITED STATES PATENTS 691,671 1/1902 Sjoo 252-1032,690,383 9/ 1956 Bradshaw 252-103 X 3,503,890 3/1970 Davisson 252-156 XFOREIGN PATENTS 20,820 6/ 1913 Great Britain 252--94 MAYER WEINBLATI,Primary Examiner US. Cl. X.R.

